以紫花地丁组培苗为试材,研究了紫花地丁在不同温度(16、10、4℃)处理下的生理指标的变化,探讨了紫花地丁对早春低温环境的耐受性,为紫花地丁在城市早春绿化中的应用提供依据。结果表明:在16、10、4℃处理下,随着处理时间的增加,紫花地丁组培苗丙二醛(MDA)含量均表现出先上升后下降最后趋于稳定的趋势,超氧化物歧化酶(SOD)活性则表现出先下降后上升最后趋于稳定的趋势,表明在低温下膜系统受到了一定的伤害,但组培苗通过提高自身抗氧化能力,减轻了低温环境对自身的伤害。不同温度处理均影响组培苗叶绿素含量,4℃处理下影响更为明显,但紫花地丁可在一定程度上恢复其叶绿素含量。上述温度处理下,Fo较未处理时均无明显变化,Fv/Fm整体均呈下降趋势,但随着处理时间的延长,Fv/Fm出现了波动和回升,表明低温对PSⅡ反应中心产生了的一定损害,但这种损害可能是可逆的;qP值较未处理时皆有所下降,但随着处理时间的延长qP值出现起伏波动和回升现象,而qN值较未处理时均有所升高,表明了紫花地丁在低温环境下可通过增强接收电子的能力和增加光合系统的热耗散来减轻低温环境对自身的伤害。上述生理指标变化表明紫花地丁对低温(4~16℃)具有较好的耐受性。 The tissue culture seedlings of Viola yedoensis were used as materials to study the changes of physiological indexes of Viola yedoensis under different temperatures (16, 10, and 4 ℃), and the tolerance of Viola yedoensis to low temperature in early spring was studied Violet land in the city in early spring greening application basis. The results showed that under the treatment of 16, 10, and 4 ℃, the content of malondialdehyde (MDA) in the tissue culture seedlings of Viola yedoensis increased first and then decreased and finally tended to be stable with the increase of treatment time. The superoxide dismutase The activity of SOD showed the trend of first decreasing and then stabilizing, which indicated that the membrane system was harmed at low temperature. However, the tissue culture seedlings could reduce their damage caused by low temperature environment by increasing their antioxidant capacity. The effects of different temperature treatments on chlorophyll content of tissue culture seedling were more obvious under the treatment of 4 ℃, but the content of chlorophyll could be restored to some extent by Viola yedoensis. Under the above temperature treatment, there was no significant change in F o / Fm and the overall Fv / Fm showed a downward trend. However, with the increase of treatment time, Fv / Fm fluctuated and recovered, indicating that the low temperature produced a However, this damage may be reversible. The qP values ​​decreased as compared with the untreated ones. However, qP values ​​fluctuated and recovered with the increase of the treatment time, while qN values ​​increased as compared with the untreated ones High, indicating that Viola yedo in low temperature environment by increasing the ability to receive electrons and increase the heat dissipation of the photosynthetic system to reduce the damage of low temperature environment on their own. The above physiological changes indicate that Viola yedo has good tolerance to low temperature (4 ~ 16 ℃).